Abstract T P47: Response to Thrombolysis in Ischemic Stroke Depends on the Presence of Initial Arterial Occlusion
Objective: We aimed to assess effectiveness of intravenous thrombolysis (IVT) for acute ischemic stroke (AIS) depending on the presence or absence of cervical or intracranial arterial occlusion on acute CT angiography (CTA).
Methods: Patients from the Acute STroke Registry and Analysis of Lausanne (ASTRAL) were included in the analysis if they had an onset-to-door-time ≤ 4hours, CTA within 24 hours of onset, premorbid modified Rankin scale (mRS) ≤ 2, and a National Institute of Health Stroke Scale score (NIHSS) >4. Patients having significant intracranial stenosis (50-99%) or receiving endovascular treatment were excluded. The primary outcome was a 3 month handicap of mRS >2. We used an interaction analysis of IVT and initial arterial occlusion after adjusting for potential confounders for the primary outcome.
Results: Of 655 included patients, 382 patients (58%) showed arterial occlusion, of whom 263 (69%) received IVT. Of the 273 patients without arterial occlusion, 139 (51%) received IVT.
In patients with initial arterial occlusion and after multiple adjustments, IVT was associated with lower likelihood of unfavourable outcome (adjusted OR 0.33, 95% CI 0.12-0.91, p=0.03) whereas it had no significant effect in non-occluded patients (OR 1.32, 95% CI 0.36-4.76, p=0.67). Similarly, the presence of arterial occlusion did not significantly worsen the outcome in thrombolysed patients (OR 1.99, 95% CI 0.68-5.81, p=0.21), whereas it did so in non-thrombolysed patients (OR 7.89, 95% CI 2.29-27.25, p<0.01).
Conclusions: IVT for AIS is more effective in the setting of visible arterial occlusions on acute imaging. If confirmed in other studies, this information may influence thrombolysis decisions and planning of further randomized trials.
Classification of evidence: This retrospective analysis provides class III evidence that IVT has less benefit in patients without visible occlusion on acute CTA.
Author Disclosures: F. Medlin: None. M. Amiguet: None. P. Vanacker: None. P. Michel: None.
- © 2014 by American Heart Association, Inc.